Objective: Metabolic syndrome (MetS) is prevalent among antipsychotic-treated patients; however, in psychiatric clinics, scarce resources often limit the feasibility of monitoring all 5 criteria that are necessary for diagnosing MetS. As one goal of the MetS definition is to facilitate the clinical identification of insulin-resistant individuals, other biomarkers of insulin resistance have been explored. However, there are relatively few data from antipsychotic-treated patients, especially on the association between these markers and the clinical MetS diagnosis.

Method: We analyzed data from 196 psychiatric patients over age 40 years enrolled in an ongoing study of antipsychotic-related metabolic effects that began in August 2005. In addition to anthropometric measures and MetS criteria, levels of certain metabolism-related peptides (ghrelin, adiponectin, peptide YY, leptin, and insulin) were measured. The utility of these clinical and metabolic markers to identify individuals with MetS was evaluated by constructing receiver operating characteristic curves. Optimal cutoff values were calculated for markers with the greatest area under the curve on the basis of sensitivities and specificities for MetS diagnosis.

Results: Ninety-nine subjects (50.5%) met MetS criteria. The receiver operating characteristic analysis found that waist circumference, triglyceride to high-density lipoprotein (TG:HDL) ratio, and body mass index had the greatest area under the curve. The waist circumference cutoff value of 40 inches, TG:HDL ratio of 2.6, and body mass index of 28 kg/m2 yielded sensitivities and specificities of 73% and 80%, 74% and 78%, and 75% and 74%, respectively, for MetS diagnosis.

Conclusions: Waist circumference, TG:HDL cholesterol ratio, or body mass index could be used as screens for identifying possible MetS in antipsychotic-treated patients to prompt complete investigation into all MetS criteria.